That is a great picture! VERY helpful!
I was thinking this would be a endocrine alopecia - common in this breed.
NOT what your picture is showing.
This is more indicative of a deep skin infection (pyoderma) otherwise called a moist dermatitis.
This conditionl although at times related to many factors is commonly caused by allergies.
Since allergies are commonly found in these cases, I would recommend starting an antihistamine, Benadryl - The dose will be 1mg for every 1 pound of body weight. For example, a 25 pound dog should receive 25mg of benadryl. You can start and then give a dose every 8 to 12 hours thereafter. Please be certain it is the product consisting of only Diphenhydramine and DOES NOT CONTAIN ANY OTHER INGREDIENTS SUCH AS A DECONGESTANT.
Along with benadryl it is recommended to clean the area itself. If possible, shaving with clippers (not scissors) is recommended to remove hair and debris. Please do not use scissors as you can accidentally cut the skin.
Then I would recommend purchasing a Chlorhexiderm shampoo, or other type of antibacterial shampoo from your local pet store to wash and scrub the area.
If she is licking the area, getting an e-collar from the pet store is also recommended to prevent further self-trauma. The E-collar should be used until the skin is healed which may take 7-10 days.
Once cleaned, you can use topical neosporin on the area twice daily.
If the skin does not heal well, or looks worse with the therapy above, there are times when a dog will need systemic antibiotics, which you can discuss with your veterinarian...
But i hope the above information is helpful in making your dog feel better!______________________________________________________________________________
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